9. Wash, rinse, repeat

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Here’s a great example of how to spend the money saved by following our No. 10 tip to maintain your car. Let’s say you save $0.30 a gallon by skipping unnecessarily high-octane gas and filling with regular. If you have a 20-gallon tank, that’s an instant $6 saved with every fill-up; that’s enough for a basic car wash in many places. Regular washing and waxing preserves paint and prevents rust from gaining a foothold. Remember to show the interior some love too, by vacuuming and detailing.